undo

adj

1. Misspelling of undue.

noun

Etymology: From Middle English undōn, from Old English ondōn, from Proto-West Germanic *andadōn (“to undo”), equivalent to un- + do. Cognate with West Frisian ûndwaan, ûntdwaan (“to undo; rid”), Dutch ontdoen (“to undo”).

1. An operation that reverses a previous action.

   “How many undos does this program support?”

verb

Etymology: From Middle English undōn, from Old English ondōn, from Proto-West Germanic *andadōn (“to undo”), equivalent to un- + do. Cognate with West Frisian ûndwaan, ûntdwaan (“to undo; rid”), Dutch ontdoen (“to undo”).

1. To reverse the effects of an action.

   “Fortunately, we can undo most of the damage to the system by the war.”

   “What's done can't be undone.”

2. To unfasten.

   “Could you undo my buckle for me?”

3. To unfasten the clothing of (a person).

   “PROSTITUTE: Undo me. There's a dear.”

4. To impoverish or ruin, as in reputation; to cause the downfall of.

   “Woe is me, for I am undone!”